Process for low-temperature distillation of bituminous coal



April 9, 1929. G. ROHMER PROCESS FOR LOW TEMPERATURE DISTILLATION OF BITUMINOUS GOAL Filed April 23, 1927 2 Sheets-Sheet fizvevvr: GaEra'eZEEOZ/uaen April 1929- G. E. ROHMER 1,708,740

PROCESS FOR LOW TEMPERATURE DISTTLLATION OF BITUMINOUS COAL Filed April 23, 1927 2 Sheets-Sheet 2 ,Bwe 71260 r.- aaare'elflj okwzer,

Patented Apr. 9, 1929.

UNITED STATES GABRIEL E. ROHMER, OF NEW YORK, Y., ASSIGNOR TO NATIONAL GOAL DISTILLA- Y TION CORPORATION.

PROCESS FOR LOW-TEMPERATURE DISTILLATION OF BITUMINOUS COAL.

Application filed April 23,

My invention relates to an improved and novel process for the low tem erature distillation or carbonization o bituminous coals.

The prime object of this invention is to provide a novel, simple, and thoroughly eflieient process for the low temperature d1stillation of bituminous coals, whereby a .high grade and greater volume of gas can be produced than by any process of equal proportions that is now employed in the manufacture of such gas; and at the same time obtaining from said material all of its most 'valuable by-produots.

Another object of the invention in carrying out the process is to so construct my 1mproved distillation retort that high volatile coals will readily yield their most valuable by-products at relatively low distillation temperatures (between 300 C and 600 C.)

so that the amount of volatile matters contain ed in the resulting semi-coke can be easily controlled, thus permitting the production of coal residues containing enough volatile matters to allow their utilization as smokeless fuels, and so as to utilize the heat conducting qualities of certain metals, such as lead, tin or other low-melting point non-ferrous elements by the use of flasks 0 or vessels filled with suitable quantities of said metals, said flasks or vessels being disposed. within the inner and outer pair of casings of the retort, thereby radiating the absorbed heat, and producing an easily con- 5 trollable temperature within the distillation chamber.

A further object of the invention is to so conduct my improved process that a given body of the material undertreatment will be fed step by step, or alternately advanced and retarded, as it is caused to be fed through the distillation chamber and at the same time simultaneously subjected to a' different temperature from opposite sides 5 of said chamber.

The foregoing and such other objects as may appear from the ensuing description are accomplished by the construction, arrangement, combination and location of the parts which constitute an embodiment of my invention by which the process may be carried out and will now be described with reference to the accompanying drawings, after which vation of the apparatus employed in carrying out my invention, and

Figure 2 is a transverse section taken in the plane of the dotted lines 22, Fig.1.

In the embodiment of my invention as illustrated, it will be seen that the numeral 1 designates a concrete foundation, although any desirable material may be utilized in the construction of said foundation for the support of the refractory structure 2 at the base in which are arranged the compartments 3. In each of these compartments and above the retort the burners 4 are so disposed as to generate the heat required for the process of low temperature distillation or carbonlzation.

The retort 5 is drum-shaped, and composed of a plurality of cylindrical casings 6 7, 11 and 12 forming the annular distillation chamber 8, and between said cas ings 6 and 11 are disposed steel flasks or vessels 9, While other steel flasks or vessels 9 are disposed between the casings 7 and 12, each of said flasks or vessels being filled with lead, hermetically sealed, and housed within the channel members 10, which are riveted to the casings 6 and 11 and 7 and 12, respectively, said casings being secured together as a rigid unit by the brackets 52' At the discharge end of theretort is fixedly secured a tire rim 13, adapted to engage with the rollers 15 and at the opposite end of said retort is rigidly secured a gear tire rim 14, and the pinion 16 keyed to the shaft 17, and driven by the pulleys 18 and 19, for imparting the motive power required to revolve the retort.

The combustion chamber built around the retort has its walls filled in with a suitable insulating material 20, and supports an arch 50 provided at its top with exhaust outlets 21, fitted with regulators 22, and leading to the flue 23, through which the combustion gases generated by the burners is allowed to escape.

Embedded at their bases in the concrete foundation are suitable buckstays 24, adapted to furnish the necessary reinforcements the circular asbestos flaps 51, secured to the masonry, serve as diaphragms to prevent the escape of heat and combustion gases 5 around the periphery of the retort.

The feeding end of the retort is equipped with the hopper 25, the air tight coal distributingivalve 26, a screw feed conveyor 27, a driving pulley 53, and stufling box 28,

while at the discharge end, the retort is eqTlipped with a truncated cone discharge apron 29 encased within the gas chamber 30 surmounted by a series of gas or vapor outlets 31, and a stuffing box 32 adapted to 1 render the connection between the gas chamber and the truncated discharge apron ahsolutoly air tight, a discharge air tight valve I construction of the retort are'each formed 30 in the shape of a truncated cone, with their largest diameters disposed at the discharge end of the retort, and the casing 6 forming the outer wall of the low temperature distillation chamber, is lined with angle iron ribs 39, said ribs running throughout the length of the retort and are slightly inclined inwardly along their entire lengths. To the inner wall of the low temperature distillation chamber is ,fixedlysecured the 40 flanged members 40, said wall being also providedwith parallel longitudinal anglenribs 41 extending the full length of the retort.-

The operation of my novel apparatus may be described as follows:

hopper 25 from Whence'it is distributed by the air tight valve 26 to the feed screw conveyer 27 operated by the pulley 53, and when leaving the ,conveyer the coal falls on the outer wall 6 of the low temperature distillation chamber, which is revolving, the coal being engaged and advanced by the inclined ribs 39 as it is forced to travel in a circular and longitudinal movement, so that when the point of circular gravity is reached,'as the retort revolves, theucoal is caused. to fall on the shell 7 of the low temperature distillation chamber, and, since the shell 7 is lined with the ribs 41 and members40, forming compartments in which the coal is detained while still in circular motion, said compartments serving to retard the discharge movement of the coal, thereby prolonging its ex- I posure to heat within the retort, as owing to the inclination at whichthe ribs 41 are se- The fresh coal 42 is dumped into the feedcured along the outside periphery of the inner group of cylindrical casings a gradual feed of the coal is obtained, and the material is discharged through the conical discharge 29 into the air tight valve 33, thence to the discharge screw conveyer, 34:. During the travel through the retort the coal is alternately retarded and advanced while being subjected to the distilling or desi'ccating action of the heat generated by the burners and radiating from the flasks or vessels containing the molten lead.

The caloric power of the burners is calculated to permit. a degree of heat sufiicient to not only melt the lead but also to supply gradually and in a most effective manner the surplus heat which is radiated from the lead flasks or vessels.

It will be perceived that all gases resulting from the low temperature distillation 5 action are kept from contact with the outer air by means of the stufling boxes provided at each end of the retort, and that said gases are cooled off by being forced to contact with the surface of the cooling cone extending inside the gas chamber. In this manner and by cooling the distillation gases, their expansion and flow speed are reduced, and greater efliciency will be obtainedby the equipment provided for the separation of tar and oils contained therein. By the construction with which my process of operation is carried out it will be obvious that the bituminous material as it is gradually fed through the distillation chamber by being alternately retarded'and advanced, in what may be properly termed, a step by step movement through said chamber, the said material is simultaneously sub-- jected to a different degree of distilling or desiccating action of the heat from opposite sides of the chamber, thus increasing the contact surfaces on which the low temperature distillation takes place.

Having. thus described my invention what I claim and desire to secure by Letters Patent is:

1. In a rotary retort provided with internal and external heating members and with walls which form'an annular distillation chamber the outer wall being provided with lifting battles, and the inner wall with retarding baflles, the process for the low temperaturesdistillation of coal, consisting in feeding the body of coal through said distillation chamber, alternately advancing and retarding the coal, and simultaneously subjecting the coal during its passage. to different degrees of distillation temperature from opposite sides of said chamber, whereby the gas and other by-products are obtained from said coal.

2. Ina rotary retort provided with internal and external heating members and with walls which form an annular distilsite side while retarding,

lation chamber the outer wall being provided with lifting baflles and the inner wall with retarding bafiies, the process for the low temperature distillation of coal, consisting in feeding the body ofcoal by an alternately advancing and retarding movement through said distillation chamber, and simultaneously subjecting the coal to different degrees of distillation temperature while advancing than when retarding, for obtaining the by-products from said coal.

3. In a rotary retort provided with internal and external heatingi members and with walls which form an annular distillation chamber the outer wall being provided with lifting bafiles and the inner wall with retarding bafiies, the process for the low temperature distillation of coal, consisting in feeding the coal through said distillation chamber by an alternately advanced and retarded movement and simultaneously subjecting the coal to a diiferent degree of distillation temperature from one side while advancing and from the oppofor obtaining the by-products from said coal.

4. In a rotary retort provided with internal and external heating members and with walls which form an annular distillation chamber the outer wall being provided with lifting baflles and the inner wall with retarding battles, the process for the low temperature distillation of coal, consisting in feeding the body of coal through said distillation chamber by an alternately advanced and retarded movement, simultaneously subjecting the coal to a different degree of distillation temperature from one side while advancing and from the opposite side while retarding, and subjecting the escaping gas to a cooling action as it escapes from one end of said chamber.

5. In a rotary retort provided with internal and external heating members and witln walls which form an' annular distillation chamber the outer wall being provided with lifting battles and the inner wall with retarding battles, the process for the low temperature distillation of coal con sisting in a gradual alternately advancin and retarding movement of the coal throug said distillation chamber, simultaneously subjecting the coal to a different degree of distillation temperature obtained from one side while advancing and from the opposite side while retarding, and subjecting the gas emanating from the outlet end of the chamber to a cooling action.

6. In a rotary retort provided with internal and external heating members and with walls which form an annular distillation chamber the outer wall being provided with lifting bafiles and theinner wall with retarding baflles, the process for the low temperature distillation of bituminous coal for making gas and obtaining its byproducts, consisting in feeding the body of coal into one end of said distillation chamber, passing it through said chamber with an alternately advancing and retarding movement, simultaneously subjecting the coal during its passage to a different degree 'of distillation temperature obtained from one side while advancing and from the 'op posite side while retarding, subjecting the gas when it has been passed through the other end of said chamber to a cooling surface, and leading off the tar and oily products therefrom.

7. In a rotary retort provided with internal and external heating members and with Walls which form an annular distillation chamber the outer wall being provided with lifting bafiles and the inner wall with retarding baflles, the process for the low temperature distillation of bituminous coal, consisting in feeding the body of coal by an alternately advanced and retarded movement through said distillation chamber, simultaneously subjecting the coal to a different degree of distillation temperature obtained from one side while advancing and from the opposite side while retarding, passing the gas escaping from the coal at one end of the chamber into contact with a cooling mechanism, and leading off the tar and oil products therefrom.

GABRIEL E. ROHMER. 

